Honestly, how has Kagiso Rabada not taken a wicket in this spell after lunch?!

Steve Smith offers no shot, and the ball jags back sharply to graze over the top of the stumps yet again.

  • Aus 109-4

    Steve Smith is doing that very annoying thing where he shuffles right across his stumps, convincing everyone that he's going to be trapped plumb lbw, only to whip it away with ease.

    Every time.

  • How's stat?!

    Andy Zaltzman
    Test Match Special statistician

    Steve Smith pointsPA Media

    On this ground Steve Smith has 576 runs. He's made those runs in the Ashes, a game against Pakistan in 2010 and here today.

    It is the most runs made by a non-England batter at Lord's - a record that has stood for nearly a hundred years.

  • Aus 104-4

    Beau Webster survives the rest of the over. How much longer can Kagiso Rabada keep going in this spell?

    Here's the lbw chance that South Africa missed earlier.

  • 50 runs

    50 for Steve Smith

    Aus 104-4

    Short, wide and a gift for Steve Smith to bring up his half-century.

    He flays the ball over the slips for four, reaching fifty from 76 balls.

    A single next ball brings Beau Webster back on strike to Kagiso Rabada...

  • Aus 99-4

    Lungi Ngidi replaces Marco Jansen and this could be Beau Webster's opportunity to take some pressure off himself.

    And right on cue, he drives off the back foot for four. Frustrating for South Africa.

  • Sir Alastair Cook
    Ex-England captain on BBC Radio 5 Sports Extra

    There's nothing more frustrating than knowing you should have Beau Webster out and there was barely even an appeal.

  • Jonathan Agnew
    BBC Chief Cricket Commentator on Test Match Special

    Beau Webster is showing real signs of jitters here.

    I suspect it can feel like a very lonely space when you're Webster at the moment. Test cricket is tough.

    He's hanging on in there and he's riding his luck right now.

    Beau WebsterGetty Images

  • Aus 94-4

    Kagiso Rabada is fired up here and he's a delight to watch in this kind of mood.

    He is probably seething after missing that review off Beau Webster and responds by nipping one between bat and pad, again just centimetres away from the edge.

    Webster dabs into the off side and sets off for a single in desperation to get off strike, but Smith is having none of it. Somehow, the batter survives the over.

    A gripping battle.

  • Get Involved

    #bbccricket, via WhatsApp on 03301231826 or text 81111 (standard network charges apply)

    On the subject of Test team height, Jansen and Bavuma would average well under 6ft. England's 2005 Ashes team was pretty tall with Trescothick, Vaughan, KP, Flintoff and Harmison.

    John, Sheffield

  • Aus 94-4

    Marco Jansen holds hand on headRex Features

    Marco Jansen has been metronomic since lunch.

    He beats Steve Smith on the drive before forcing him back in his crease with a fiery short ball to conclude another maiden.

  • 'It's like La Liga not having Barcelona v Real Madrid'

    Pat Cummins and Kagiso RabadaGetty Images

    While Australia and South Africa battle it out to be crowned the best Test team in the world, BBC Sport's Timothy Abraham has been investigating the financial future of the longest format.

    Tim has spoken to key stakeholders in the game for their opinions and you can read it here.

    Among the topics discussed is the World Test Championship, which has been criticised for not having the biggest game of all: India versus Pakistan.

    "We have a WTC where if you're being really honest, the most valuable fixture - India versus Pakistan - within that league never happens. It's like having La Liga but Barcelona and Real Madrid not playing each other," said former West Indies chief executive Johnny Grave.

  • Vic Marks
    Former England spinner on BBC Radio 5 Sports Extra

    Beau Webster is a lucky man at the moment because he should've been gone to Kagiso Rabada.

    Extraordinary.

  • Aus 94-4

    Now then!

    Beau Webster is trapped in front again, there's a half-hearted appeal from Kagiso Rabada and the slips but they withdraw it, perhaps assuming he'd got an edge.

    However, replays show there was no bat and it was crashing into middle stump. Oh, what a miss.

    A reprieve for Webster on eight.

  • Aus 94-4

    What do I know?

    Beau Webster unveils a picture-perfect cover drive off Kagiso Rabada for his first boundary.

  • Aus 90-4

    Not the most convincing start from Beau Webster, this.

    He gets a streaky pull shot away for two before luckily inside-edging on to his pad to get off strike.

    Quite the opposite from Steve Smith, though - he carves four more past cover to go to 45.

    An eventful over from Marco Jansen.

  • Jim Maxwell
    BBC Test Match Special commentator at Lord's

    How's that not out? It's certainly hitting the stumps.

  • Not out

    The ball is going on to hit the stumps, but it's umpire's call on impact.

    Cue the debate...

  • Vic Marks
    Former England spinner on BBC Radio 5 Sports Extra

    I thought the previous shout was a better one. He's a big man. Is height the issue here?

  • SA review

    But he reviews this time.

    Webster is trapped in front...